A variety of techniques have been employed in an attempt to make floppy disks and other similar types of media difficult to copy. However, in most if not all known types of techniques corresponding methods have been devised to defeat the protection scheme, thus allowing an unauthorized duplication of the data contents of the disk.
Although a lack of a secure technique to prevent unauthorized copying of floppy disks is a serious problem to publishers of software this lack of secure technique presents an even greater problem for those who wish to implement a computer-based value printing system, such a postage meter. For example, a desirable type of postage meter would be software based and would be implemented on a personal computer. A postage meter software package would include an application program as well as a secure "vault" program for dispensing postage and for maintaining accounting information, including the ascending and descending postage registers. However, this desirable type of system has until now been impractical to implement in that a user of the system could employ known duplication techniques to replicate the postage vault software, thereby dispensing potentially limitless amounts of unauthorized postage.
Methods for preventing this type of fraud include requiring the postal authority to account for each metered letter that enters the mail stream, or requiring the meter user to install special vault hardware for providing the accounting function. However, neither of these approaches represents an optimal solution. For example, the former approach would place an undue data processing burden on the postal authority while the latter approach would increase both the cost and complexity of the resulting postage meter system.
It is thus an object of the invention to provide apparatus for implementing a secure data processing recording media such as a floppy disk.
It is another object of the invention to provide apparatus for implementing a secure data processing recording media that includes embedding a data processing unit within the media, the unit including a device for bidirectionally communicating with a host system through a read/write head of a conventional media drive.
It is one further object of the invention to provide apparatus for implementing a secure value printing system with a personal-type computer system that includes a data processing unit embedded within a removable-type of magnetic recording media, the unit including a device for bidirectionally communicating with a host system through a read/write head of a conventional media drive and further including a secure, nonvolatile memory for maintaining at least the accounting data therein.